Bill, taking your last notes first ...
The Tarahumara Indians from Northern Mexico didn't get a heart disease risk increase -- as measured by the gold standard TOTAL : HDL ration (3.78 both before -- and after -- dietary change). In fact, according to another highly-relevant indice of heart disease risk, the triglyceride-to-HDL ratio -- they IMPROVED (from 2.84 to 2.57)!
Here's more ...
========================= J Nutr. 2006 Feb;136(2):384-9.
Carbohydrate restriction alters lipoprotein metabolism by modifying VLDL, LDL, and HDL subfraction distribution and size in overweight men.Department of Nutritional Sciences, University of Connecticut, Storrs, CT 06269, USA.
In contrast plasma HDL-cholesterol concentrations were increased by 12% (P<0.05). Changes in plasma TG were positively correlated with reductions in large (r=0.615, P<0.01) and medium VLDL particles (r=0.432, P<0.05) and negatively correlated with LDL diameter (r=-0.489, P<0.01). Changes in trunk fat were positively correlated with medium VLDL (r=0.474, P<0.0) and small LDL (r=0.405, P<0.05) and negatively correlated with large HDL (r=-0.556, P<0.01).
We conclude that weight loss induced by CR favorably alters the secretion and processing of plasma lipoproteins, rendering VLDL, LDL, and HDL particles associated with decreased risk for atherosclerosis and coronary heart disease.
PMID: 16424116 [PubMed - indexed for MEDLINE] =========================
Recap: Restricting carbs (even if it means an increase in saturated fat intake -- and it almost universally does) is heart-healthy.
========================= JAMA. 2005 Nov 16;294(19):2455-64.
Effects of protein, monounsaturated fat, and carbohydrate intake on blood pressure and serum lipids: results of the OmniHeart randomized trial.- Appel LJ,
- Sacks FM,
- Carey VJ,
- Obarzanek E,
- Swain JF,
- Miller ER 3rd,
- Conlin PR,
- Erlinger TP,
- Rosner BA,
- Laranjo NM,
- Charleston J,
- McCarron P,
- Bishop LM;
- OmniHeart Collaborative Research Group.
Welch Center for Prevention, Epidemiology and Clinical Research, Division of General Internal Medicine, Johns Hopkins University School of Medicine, Baltimore, Md 21205-2223, USA. lappel@jhmi.edu
Compared with the carbohydrate diet, the unsaturated fat diet decreased systolic blood pressure by 1.3 mm Hg (P = .005) and by 2.9 mm Hg among those with hypertension (P = .02), had no significant effect on low-density lipoprotein cholesterol, increased high-density lipoprotein cholesterol by 1.1 mg/dL (0.03 mmol/L; P = .03), and lowered triglycerides by 9.6 mg/dL (0.11 mmol/L; P = .02). Compared with the carbohydrate diet, estimated 10-year coronary heart disease risk was lower and similar on the protein and unsaturated fat diets.
CONCLUSION: In the setting of a healthful diet, partial substitution of carbohydrate with either protein or monounsaturated fat can further lower blood pressure, improve lipid levels, and reduce estimated cardiovascular risk.
Clinical Trials Registration ClinicalTrials.gov Identifier: NCT00051350.
PMID: 16287956 [PubMed - indexed for MEDLINE]
=========================
Recap:
Lower carbs = lower risk.
=========================
Metabolism. 2005 Sep;54(9):1133-41.
Weight loss associated with reduced intake of carbohydrate reduces the atherogenicity of LDL in premenopausal women.Department of Nutritional Sciences, University of Connecticut, Storrs, CT 06269, USA.
Likewise, apolipoproteins B and E decreased by 4.5% and 15% (P<.05) after 10 weeks. The LDL mean particle size was increased from 26.74 to 26.86 nm (P<.01), and the percent of the smaller LDL subfraction (P<.05) was decreased by 26.5% (P<.05) after 10 weeks. In addition, LDL lag time increased by 9.3% (P<.01), and LDL conjugated diene formation decreased by 23% (P<.01), indicating that the susceptibility of LDL to oxidation was decreased after the intervention.
This study suggests that moderate weight loss (<5% of body weight) associated with reduced caloric intake, lower dietary carbohydrate, and increased physical activity impacts the atherogenicity of LDL.
PMID: 16125523 [PubMed - indexed for MEDLINE]
=========================
Recap:
Lower carbs = lower risk.
=========================
Eur J Clin Nutr. 2005 Oct;59(10):1142-8.
A low-protein diet exacerbates postprandial chylomicron concentration in moderately dyslipidaemic subjects in comparison to a lean red meat protein-enriched diet.School of Public Health, Australian Technology Network Centre for Metabolic Fitness, Curtin University of Technology, Perth, Australia. j.Mamo@curtin.edu.au
However, subjects who consumed a low-protein diet for 6 weeks had a substantially exaggerated postprandial chylomicron response, indicated as the area under the apo B48 curve following a fat challenge. The change in postprandial chylomicron kinetics could not be explained by changes in insulin sensitivity, which appeared to be similar before and after intervention with either diet.
CONCLUSIONS: Daily moderate consumption of a lean red meat protein-enriched diet attenuates postprandial chylomicronaemia in response to ingestion of a fatty meal.
PMID: 16015257 [PubMed - indexed for MEDLINE]
=========================
Recap: Lean red meat is "health-food."
========================= Am J Clin Nutr. 2005 Jun;81(6):1298-306.
Effect of an energy-restricted, high-protein, low-fat diet relative to a conventional high-carbohydrate, low-fat diet on weight loss, body composition, nutritional status, and markers of cardiovascular health in obese women.CSIRO Health Sciences and Nutrition, Adelaide, Australia. manny.noakes@csiro.au
Serum vitamin B-12 increased 9% with the HP diet and decreased 13% with the HC diet (P < 0.0001 between diets). Folate and vitamin B-6 increased with both diets; homocysteine did not change significantly. Bone turnover markers increased 8-12% and calcium excretion decreased by 0.8 mmol/d (P < 0.01). Creatinine clearance decreased from 82 +/- 3.3 to 75 +/- 3.0 mL/min (P = 0.002).
CONCLUSION: An energy-restricted, high-protein, low-fat diet provides nutritional and metabolic benefits that are equal to and sometimes greater than those observed with a high-carbohydrate diet.
PMID: 15941879 [PubMed - indexed for MEDLINE]
=========================
Recap:
High-protein diets are "healthier" than high-carbohydrate diets are.
=========================
Diabetologia. 2005 Jan;48(1):8-16.
Comparison of high-fat and high-protein diets with a high-carbohydrate diet in insulin-resistant obese women.Edgar National Centre for Diabetes Research, Medical and Surgical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand. kirsten.mcauley@stonebow.otago.ac.nz
CONCLUSIONS/INTERPRETATION: In routine practice a reduced-carbohydrate, higher protein diet may be the most appropriate overall approach to reducing the risk of cardiovascular disease and type 2 diabetes. To achieve similar benefits on a HC diet, it may be necessary to increase fibre-rich wholegrains, legumes, vegetables and fruits, and to reduce saturated fatty acids to a greater extent than appears to be achieved by implementing current guidelines. The HF approach appears successful for weight loss in the short term, but lipid levels should be monitored. The potential deleterious effects of the diet in the long term remain a concern.
PMID: 15616799 [PubMed - indexed for MEDLINE]
=========================
Recap:
High-protein diets appear to be the most appropriate types of diets for heart disease and diabetes.
=========================
Diabetes. 2004 Sep;53(9):2375-82.
Effect of a high-protein, low-carbohydrate diet on blood glucose control in people with type 2 diabetes.Metabolic Research Laboratory (111G), VA Medical Center, One Veterans Drive, Minneapolis, MN 55417, USA. ganno004@umn.edu
We refer to this as a low-biologically-available-glucose (LoBAG) diet. Eight men were studied using a randomized 5-week crossover design with a 5-week washout period. The carbohydrate:protein:fat ratio of the control diet was 55:15:30. The test diet ratio was 20:30:50. Plasma and urinary beta-hydroxybutyrate were similar on both diets. The mean 24-h integrated serum glucose at the end of the control and LoBAG diets was 198 and 126 mg/dl, respectively. The percentage of glycohemoglobin was 9.8 +/- 0.5 and 7.6 +/- 0.3, respectively. It was still decreasing at the end of the LoBAG diet. Thus, the final calculated glycohemoglobin was estimated to be approximately 6.3-5.4%. Serum insulin was decreased, and plasma glucagon was increased. Serum cholesterol was unchanged.
Thus, a LoBAG diet ingested for 5 weeks dramatically reduced the circulating glucose concentration in people with untreated type 2 diabetes. Potentially, this could be a patient-empowering way to ameliorate hyperglycemia without pharmacological intervention. The long-term effects of such a diet remain to be determined.
PMID: 15331548 [PubMed - indexed for MEDLINE]
=========================
Recap:
Lowering glucose availability (ie. eating more protein and fat -- and less carbs) improves diabetic outcomes.
=========================
Diabetes Res Clin Pract. 2004 Sep;65(3):235-41.
Beneficial effect of low carbohydrate in low calorie diets on visceral fat reduction in type 2 diabetic patients with obesity.Center of Diabetes, Endocrine and Metabolism, Sakura Hospital, School of Medicine, Toho University, 564-1 Shimoshizu, Sakura-City, Chiba 285-0841, Japan.
There was a larger decrease in visceral fat area measured by computed tomography in the low carbohydrate diet group compared to the high carbohydrate diet group (-40 cm(2) versus -10 cm(2), P < 0.05). The ratio of visceral fat area to subcutaneous fat area did not change in the high carbohydrate diet group (from 0.70 to 0.68), but it decreased significantly in the low carbohydrate diet group (from 0.69 to 0.47, P < 0.005).
These results suggest that, when restrict diet was made isocaloric, a low calorie/low carbohydrate diet might be more effective treatment for a reduction of visceral fat, improved insulin sensitivity and increased in HDL-C levels than low calorie/high carbohydrate diet in obese subjects with type 2 diabetes mellitus.
PMID: 15331203 [PubMed - indexed for MEDLINE]
=========================
Recap:
Low-carbs is better than high-carbs -- even when controlling for total calories.
=========================
J Nutr. 2003 Sep;133(9):2756-61.
An isoenergetic very low carbohydrate diet improves serum HDL cholesterol and triacylglycerol concentrations, the total cholesterol to HDL cholesterol ratio and postprandial pipemic responses compared with a low fat diet in normal weight, normolipidemic women.Department of Kinesiology, University of Connecticut, Storrs, CT 06269-1110, USA. jvolek@uconnvm.uconn.edu
Compared with the low fat diet, the very low carbohydrate diet increased (P <or= 0.05) fasting serum total cholesterol (16%), LDL cholesterol (LDL-C) (15%) and HDL-C (33%) and decreased serum triacylglycerols (-30%), the total cholesterol to HDL ratio (-13%) and the area under the 8-h postprandial triacylglycerol curve (-31%). There were no significant changes in LDL size or markers of inflammation (C-reactive protein, interleukin-6, tumor necrosis factor-alpha) after the very low carbohydrate diet.
In normal weight, normolipidemic women, a short-term very low carbohydrate diet modestly increased LDL-C, yet there were favorable effects on cardiovascular disease risk status by virtue of a relatively larger increase in HDL-C and a decrease in fasting and postprandial triaclyglycerols.
PMID: 12949361 [PubMed - indexed for MEDLINE]
=========================
Recap:
Low-carb dieting decreased CVD risk -- as measured by the gold standard TOTAL : HDL ratio -- over-and-above that risk associated with low-fat dieting.
=========================
N Engl J Med. 2003 May 22;348(21):2082-90.
A randomized trial of a low-carbohydrate diet for obesity.University of Pennsylvania School of Medicine, Philadelphia, PA 19104-3309, USA. fosterg@mail.med.upenn.edu
CONCLUSIONS: The low-carbohydrate diet produced a greater weight loss (absolute difference, approximately 4 percent) than did the conventional diet for the first six months, but the differences were not significant at one year. The low-carbohydrate diet was associated with a greater improvement in some risk factors for coronary heart disease. Adherence was poor and attrition was high in both groups. Longer and larger studies are required to determine the long-term safety and efficacy of low-carbohydrate, high-protein, high-fat diets.
Copyright 2003 Massachusetts Medical Society
PMID: 12761365 [PubMed - indexed for MEDLINE]
=========================
Recap:
Low-carb dieting was associated with greater improvement in some risk factors (than conventional dieting was).
=========================
J Nutr. 2003 Feb;133(2):411-7.
A reduced ratio of dietary carbohydrate to protein improves body composition and blood lipid profiles during weight loss in adult women.Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. d-layman@uiuc.edu
Both groups had significant reductions in serum cholesterol ( approximately 10%), whereas the Protein Group also had significant reductions in triacylglycerols (TAG) (21%) and the ratio of TAG/HDL cholesterol (23%). Women in the CHO Group had higher insulin responses to meals and postprandial hypoglycemia, whereas women in the Protein Group reported greater satiety. This study demonstrates that increasing the proportion of protein to carbohydrate in the diet of adult women has positive effects on body composition, blood lipids, glucose homeostasis and satiety during weight loss.
PMID: 12566476 [PubMed - indexed for MEDLINE]
=========================
Controlled-carb diets are better for chicks.
Ed
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